Although the total “Timed-Up-and Go” test (TUG) performance time can characterize an age-related decline of general mobility, this result alone doesn’t give any detailed information about the test subtasks. The primary objective of the study was to identify in nursing home women a variable extracted from instrumented TUG (iTUG) that is the best predictor of age. The secondary objective was to assess whether this variable is associated with the results of the isometric knee extension peak torque (IKEPT); lower limb strength measured by the 30-s chair stand test (30sCST), and walking capacity measured by the 6-min walk test (6MWT). Twenty-six women (mean ± SD: age—85.8 ± 3.6 years; body weight—59.4 ± 12.3 kg; body height—151.0 ± 7.3 cm; BMI—26.0 ± 4.9 kg/m2) performed iTUG (while wearing a body-fixed inertial sensor) and functional tests. Total iTUG performance time significantly correlated with age (r = 0.484; p < 0.05), 30sCST (r = −0.593; p < 0.01), and 6MWT (r = −0.747; p < 0.001) but not with absolute nor relative IKEPT (p > 0.05). Additionally, the subjects’ age correlated with 30sCST (r = −0.422; p < 0.05), 6MWT (r = −0.482; p < 0.05), IKEPT (r = −0.392; p < 0.05) and IKEPT/FFM (r = −0.407; p < 0.05). Five out of 16 analyzed iTUG variables were significantly related to age, and multiple regression analysis showed the best correlation with the sit-to-stand vertical acceleration range (STSVAR) (r2 = 0.430; SEE = 3.041; β = −0.544 ± 0.245; B = −1.204 ± 0.543; p < 0.05). Moreover, STSVAR was significantly associated with %Fat (r = 0.415; p < 0.05), 30sCST (r = 0.519; p < 0.01), 6MWT (r = 0.585; p < 0.01) but not with absolute nor relative IKEPT (p > 0.05). The obtained results suggest that in the oldest old group of nursing home women an age-related decline in TUG performance is mainly associated with a reduction of “explosive” strength of lower limb muscles.
1 July 1997 in European Journal of Applied Physiology
Objective: International guidelines recommend the use of ultrasound (US) and electrical stimulation (ES) for treating chronic and recurrent pressure ulcers (PUs). The methodology of these procedures, however, still needs elaboration and confirmation by clinical studies. This parallel-group, randomised, single-blind, prospective, controlled clinical trial was conducted to determine whether by using high-frequency ultrasound (HFUS) and high-voltage monophasic pulsed current (HVMPC), the rate of change in the area of older patients' PUs can be accelerated.Method: Patients were randomly assigned to receive either: standard wound care (SWC) involving supportive care and topical treatments; SWC+US (1MHz; 0.5 W/cm2; 20%; 1–3 minutes/cm2); or SWC+ES (HVMPC, 154 µs, 100 pps, 100 V, 250 µC/sec, 50 minutes/day). US and ES were administered once a day, 5 days a week. The primary outcome was change in PU surface area measured against baseline after 6 weeks of treatment with SWC, SWC+US, and SWC+ES.Results: We recruited 77 patients, aged 60–95 years (80% aged over 70 years of age), with 88 Category II, III and IV PUs were enrolled in the study. The percentage reduction in the surface area of PUs at the end of treatment was significantly greater in the SWC+US group (mean ± standard deviation, 77.48±11.59 %; p=0.024) and the SWC+ES group (76.19±32.83%; p=0.030) versus the control group (48.97±53.42%). The SWC+ES group also had a significantly greater proportion of PUs that decreased in area by at least 50% or closed than the control group (p=0.05 and 0.031, respectively). The SWC+US and SWC+ES groups were not statistically significant different regarding treatment results. Clinical side effects were not recorded.Conclusion: The results show that HFUS and HVMPC are comparable regarding their effectiveness in reducing the size of PUs in older people.Declaration of interest: The authors have nothing to disclose. All research activities were funded by the Academy of Physical Education, Katowice, Poland.
1 September 2002 in International Journal of Sport Nutrition and Exercise Metabolism
Skeletal muscle mitochondrial capacity (mito), tissue blood flow (BF) capacity, and oxygen exchange capacity (e.g., DO2) appear to be well matched. The different skeletal muscle fiber types and muscle remodeled, due to inactivity >(e.g., related to aging or disease) or exercise training, exhibit widely differing aerobics capacities (V̇O2max). Yet, there are remarkably coordinated alterations in these 3 parameters in each of these conditions. With such a balance, there is likely shared control among these parameters in limiting (V̇O2max) of muscle, although this is a matter of considerable debate. The reduction in aerobic capacity in elderly can be improved by submaximal aerobic exercise training; this is related to increases in muscle mitochondria concentration and capillarity, but probably not BF capacity, as this is limited by central cardiovascular function. Thus, exercise-induced biochemical adaptations and angiogenesis occur in the elderly. The increase in muscle capillarity likely contributes to the increased oxygen exchange capacity, typical of endurance type training. The increase in [mito] appears essential to realize the increased in muscle V̇O2max with training and amplifies the rate-limiting influence of the muscle’s oxygen exchange capacity. Further, vascular remodeling induced by exercise in the elderly could be effective at improving flow capacity, if limited by peripheral obstruction. Thus, the limits to aerobic function specific to aged muscle appear most influenced by inactivity, whereas central cardiovascular changes impact whole body performance. Some may consider the aged myocyte as a small, inactive, normal myocyte in need of activity!
1 June 2001 in International Journal of Sport Nutrition and Exercise Metabolism
The purpose of this study was to discover whether severe dietary carbohydrate (CHO) restriction modifies the relationship between exercise intensity and hormonal responses to exercise. Changes in the plasma adrenaline (A), noradrenaline (NA), growth hormone (hGH), testosterone (T), and blood lactate (LA) during an incremental exercise performed until volitional exhaustion were determined in 8 physically active volunteers after 3 days on low CHO (<5% of energy content; L-CHO) and isocaloric mixed (M) diets. Following L-CHO diet, the basal plasma A, NA, and hGH concentrations were increased, whilst T and LA levels were decreased. During exercise all the hormones increased exponentially, with thresholds close to that of LA. Neither the magnitude nor the pattern of the hormonal changes were affected by L-CHO diet except the NA threshold, which was lowered. Blood LA response to exercise was diminished and LA threshold was shifted towards higher loads by L-CHO diet. It is concluded that restriction of CHO intake (a) does not affect the pattern of changes in plasma A, hGH, and T concentrations during graded exercise but lowers NA threshold, indicating increased sensitivity of the sympathetic nervous system to exercise stimulus; (b) alters the basal and exercise levels of circulating hormones, which may have an impact on the balance between anabolic and catabolic processes and subsequently influence the effectiveness of training.